The isolation and identification of prostratin as an anti-HIV compound and the observation of a significant number of anti-HIV active extracts from the Euphorbiaceae led us to consider a linkage of phorbol receptor binding activity with AIDS antiviral activity. This concept of linkage has been supported by observation of anti-HIV activity in the aplysiatoxins and indolactams. A very small number of plant extracts outside the Euphorbiaceae are active in the phorbol receptor binding assay and the anti-HIV screen; from these leads we have discovered anti-HIV active triterpenes and xanthophylls.